The present invention relates to a novel tape cassette, and more particularly to a novel tape cassette which arranged to prevent slack in the tape and to prevent tape jams that max cause damage to the tape and the tape player.
A known type of tape cassette is formed with a tape drawing recess for receiving a tape loading member which draws the tape to a front surface of the cassette case.
If such a tape drawing recess is large, that is, if it extends a long distance in a lateral direction of the cassette case, there the tape disposed along the front of the tape drawing recess max become unstable.
To prevent the tape from becoming unstable, the tape cassette is provided with conventional means for locking the tape reels while the tape cassette is not being used. However, upon loading the tape cassette into a tape player, it is necessary to unlock the tape reels to allow the tape to be drawn out of the cassette case. If there is even a slight error in the timing for unlocking the tape reels unlocking, slack may be formed in the tape leading to a tape jam.
To solve this problem, it has been proposed to form a tape slack preventing member c as shown in FIG. 11. In particular, the tape slack preventing member c projects upwardly from a bottom wall of a cassette case a, and is located close to a back surface of a tape b. Accordingly, even when slack is formed in the tape b, it is possible to prevent the tape b from entering a tape drawing recess d.
A known type of tape cassette, for example, the so-called 8 mm VCR tape cassette, has a front lid e rotatably supported at a front end portion of the cassette case a for covering a front surface of the tape b and a back lid f adapted to be rotated in association with rotation of the front lid e for covering a back surface of the tape b, so as to prevent dust from sticking to the part of the tape b that is outside of the cassette case a at a time when the tape cassette is not being used. However, when both the lids e and f are open it is possible for the tape b to be displaced from its proper position.
More specifically, FIG. 11 shows a closed position in which the front and back surfaces of the tape b are covered with the lids e and f, respectively, and FIG. 12 shows an open position that results after the lids e and f are rotated together to uncover the front and back surfaces of the tape b. During the movement of the back lid f between the closed position and the open position, the attitude of the back lid f is controlled according a locus of a pivot g supported by the front lid e and a locus of a slide pin i which is guided by a guide groove h formed in the cassette case a, so that the back lid f does not contact the tape b during the movement. The locus of the slide pin i is denoted by a phantom line k.
However, as the back lid f is moved in a limited space, it is unavoidable that the back lid f comes close to the tape b. Accordingly, if the back lid f was previously charged with static electricity, a part of the tape b is lifted by the back lid f during the movement to the open position. As shown in FIG. 12, there is defined a gap j between a lower end of the back lid f and an upper end of the tape slack preventing member c when the back lid f is in the open position. As a result, the part of the tape b lifted by the back lid f may pass through the gap j and enter behind the tape slack preventing member c.
When the part of the tape b goes behind the tape slack preventing member c as mentioned above, tape jamming or damage to the tape loading member or other mechanisms occurs upon tape loading.